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Purpose: This study aimed to elucidate the treatment approach for blunt splenic injuries concurrently involving the aorta. We hypothesized that non-operative management failure rates would be higher in such cases, necessitating increased hemorrhage control surgeries., Methods: Data from the Trauma Quality Improvement Program spanning 2017 to 2019 were utilized. All patients with blunt splenic trauma were considered for inclusion. We conducted comparisons between blunt splenic trauma patients with and without thoracic or abdominal aortic injuries to identify any potential disparities in treatment., Results: Among the 32,051 patients with blunt splenic injuries during the study period, 752 (2.3%) sustained concurrent aortic injuries. Following 2:1 propensity score matching, it was determined that the presence of aortic injuries did not significantly affect the utilization of splenic transarterial angioembolization (TAE) (7.2% vs. 8.7%, p = 0.243) or the necessity for splenectomy or splenorrhaphy (15.3% vs. 15.7%, p  = 0.853). Moreover, aortic injuries were not a significant factor contributing to TAE failure, regardless of the location or severity of the injury. Patients with simultaneous splenic and aortic injuries required more red blood cell transfusion within first 4 hours (0 ml [0, 900] vs. 0 ml [0, 650], p  = 0.001) and exhibited a higher mortality rate (10.6% vs. 7.9%, p = 0.038)., Conclusion: This study demonstrated that patients with concurrent aortic and splenic injuries presented with more severe conditions, higher mortality rates, and extended hospital stays. The presence of aortic injuries did not substantially influence the utilization of TAE or the necessity for splenectomy or splenorrhaphy. Patients of this type can be managed in accordance with current treatment guidelines. Nonetheless, given their less favorable prognosis, they necessitate prompt and proactive intervention., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

At present, research on blunt abdominal aortic injury (BAAI) is limited, with the majority being case reports. Consequently, there is a significant knowledge gap concerning this condition. To address this, we conducted a systematic review by extensively searching major databases. We included all literature that provided individual (non-identifiable) data on BAAI patients, irrespective of the study design. Furthermore, we undertook regression analyses to identify predictors of death after BAAI. The search yielded 2,099 results, leading to the inclusion of 102 case reports and one conference abstract. Using the Joanna Briggs Institute (JBI) checklist for assessment, all studies were deemed of medium to high quality. In total, 133 patients were included, with a median age of 34 years, and 73.7% being male. The predominant clinical manifestation was pain, reported in 65.6% of patients. The most frequently observed aortic lesion severity was grade A (intimal tear or intramural hematoma) at 46.9%, and the most common lesion location was zone III (infrarenal aorta) in 88.3% of cases.  The overall mortality after BAAI was 15.3%. Multivariate regression analyses revealed the following predictors of death after BAAI: lower limb ischemia (relative risk [RR] = 7.137, 95% confidence interval [CI] 1.154 - 44.161), cardiopulmonary arrest (RR = 10.250, 95% CI 1.452 - 72.344), and injuries to body parts other than the abdomen and lumbar spine (RR = 2.593, 95% CI 1.189 - 5.655). In conclusion, this review provides a detailed quantitative summary of BAAI's clinical manifestations, diagnosis, treatment, and prognosis, emphasizing its high mortality rate and identifying three critical variables as predictors of death.

The patient is an 8 year-old male presenting to outside facility following high-speed motor vehicle collision in which he was a restrained passenger. CT imaging at that time demonstrated a traumatic infrarenal aortic pseudoaneurysm, extensive pneumoperitoneum and free fluid, and an unstable L2 vertebral body fracture. He underwent exploratory laparotomy with small bowel resection prior to transfer. The patient was left in discontinuity and temporary closed. Vascular surgery was consulted upon arrival to tertiary care children's hospital. The decision was made to proceed with emergent endovascular repair. An aortogram confirmed the location of the aortic disruption well below the renal arteries, superior to the bifurcation. An 11 mm × 5 cm Viabahn covered stent was placed across the injury with adequate proximal and distal seal. This is a case of seatbelt-related pediatric infrarenal aortic injury in the setting of polytrauma. Endovascular repair was pursued in this damage-control setting., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Traumatic aortic injuries in children and adolescents are rare, and even more rare are blunt traumatic injury to the abdominal aorta in this population. Therefore, there are few reports discussing the presentation and repair of such injuries, especially within the pediatric population. We report the successful repair of traumatic abdominal aortic transection in a 10-year-old female after a high speed MVC. She arrived in extremis with a seatbelt sign and was taken emergently for damage control laparotomy with subsequent postoperative CT findings of aortic transection/dissection at L3 with active extravasation. She immediately underwent open thrombectomy of the bilateral iliac arteries, and repair of her aortic injury with a 12 × 7 mm Hemashield interposition graft extending just distal to the IMA and 1 cm proximal to the aortic bifurcation. There are little data regarding long-term outcomes of pediatric patients undergoing different aortic repair techniques, and further research is needed.

Background: Studies on the mortality of blunt abdominal aortic injury (BAAI) are rare and have yielded inconsistent results. In the present study, we aimed to quantitatively analyse the retrieved data to more accurately determine the hospital mortality of BAAI., Methods: The Excerpta Medica Database, PubMed, Web of Science and Cochrane Library databases were searched to identify relevant publications without date restrictions. The overall hospital mortality (OHM) of BAAI patients was set as the primary outcome measure. English publications with data that met the selection criteria were included. The quality of all included studies was assessed by the Joanna Briggs Institute checklist and the American Agency for Health Care Quality and Research's cross-sectional study quality evaluation items. After data extraction, a meta-analysis of the Freeman-Tukey double arcsine transformation of data was performed using the Metaprop command in Stata 16 software. Heterogeneity was assessed and reported as a percentage using the I 2 index value and as a P value using the Cochrane Q test. Various methods were used to determine the sources of heterogeneity and to analyse the sensitivity of the computation model., Results: Of the 2147 references screened, 5 studies that involved 1593 patients met the selection criteria and were included. There were no low-quality references after assessment. One study that only included 16 juvenile BAAI patients was excluded from the meta-analysis of the primary outcome measure due to high heterogeneity. Due to the low heterogeneity (I 2  = 47.6%, P = 0.126 for Q test) that was observed after using the random effects model, the fixed model was subsequently used to pool the effect sizes of the remaining four studies, thus yielding an OHM of 28.8% [95% confidence interval (CI) 26.5-31.1%]. The stability of the model was verified by sensitivity analysis, and Egger's test (P = 0.339) indicated a low level of publication bias. In addition, we also performed meta-analyses and obtained a pooled hospital mortality of operation (13.5%, 95% CI 8.0-20.0%), a pooled hospital mortality of non-operation (28.4%, 95% CI 25.9-31.0%), and a pooled rate of aortic rupture (12.2%, 95% CI 7.0-18.5%) of BAAI., Conclusions: The present study indicated that BAAI has an OHM of 28.8%, indicating that this disease deserves more attention and research., (© 2023. The Author(s).)

Objective: Blunt abdominal aortic injury in children is a rare clinical entity with which most vascular surgeons have minimal experience. The evidence for management recommendations is limited. We have reported a single institution's experience in the care of pediatric abdominal aortic injuries., Methods: We performed a retrospective review of consecutive pediatric patients who had been diagnosed with blunt traumatic abdominal aortic injury at our institution from 2008 to 2019., Results: A total of 16 pediatric patients (50% male) were identified. They ranged in age from 4 to 17 years. All had been involved in motor vehicle collisions and had been restrained passengers with a seatbelt in use. Five patients (31%) were hypotensive en route or on arrival. Seven patients (44%) had been transferred from another hospital. The median injury severity score was 34 (interquartile range, 19-35). The infrarenal aortic injuries were stratified using the aortic injury grading classification (five, two, seven, and two with grade 1, 2, 3, and 4, respectively). Concurrent nonaortic injuries included solid organ (63%; n = 10), hollow viscus (88%; n = 14), brain (25%; n = 4), hemothorax or pneumothorax (25%; n = 4), spine fractures (81%; n = 13), and nonspine fractures (75%; n = 12). Of the 16 patients, 9 (56%) had required aortic repair. Three had required immediate revascularization for distal ischemia. The remaining six patients (38%) had undergone delayed repair, with a median interval to repair of 52 days (range, 2-916 days). One half of the delayed repairs were performed during the index hospitalization. On repeat axial imaging, the three patients who had undergone delayed repair were found to have enlarging pseudoaneurysms or flow-limiting dissections and had subsequently undergone repair during the index hospitalization. Only one patient had undergone endovascular repair. No deaths occurred, and the median follow-up was 7 months (interquartile range, 3-28 months) for our study population. All postoperative patients demonstrated stable imaging findings without requiring further intervention. Seven patients, whose injury grades had ranged from 1 to 3, were observed. Their repeat imaging studies demonstrated either stability or resolution of their aortic injury. However, one half of the patients had been lost to follow-up after discharge or after their first postoperative clinic visit., Conclusions: Delayed aortic intervention can be safely performed for most pediatric patients with blunt abdominal aortic injuries with preserved distal perfusion to the lower extremities. This finding suggests that transfer to a tertiary center with vascular expertise is a safe and feasible management strategy. However, the progression of aortic injuries was seen as early as within 48 hours and as late as 30 months after injury, underscoring the importance of long-term surveillance. However, in our cohort, 50% of the children were lost to follow-up, highlighting the need for a more structured surveillance strategy., (Copyright © 2022 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Limb ischemia is a major complication associated with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). The high velocity jet from arterial cannulae can cause "sandblasting" injuries to the arterial endothelium, with the potential risk of distal embolization and end organ damage. The aim of this study was to identify, for a range of clinically relevant VA-ECMO cannulae and flow rates, any regions of peak flow velocity on the aortic wall which may predispose to vascular injury, and any regions of low-velocity flow which may predispose to thrombus formation. A silicone model of the aortic and iliac vessels was sourced and the right external iliac artery was cannulated. Cannulae ranged from 15 to 21 Fr in size. Simulated steady state ECMO flow rates were instituted using a magnetically levitated pump (CentriMag pump). Adaptive particle image velocimetry was performed for each cannula at 3, 3.5, 4, and 4.5 L/min. For all cannulae, in both horizontal and vertical side hole orientations, the peak velocity on the aortic wall ranged from 0.3 to 0.45 m/s, and the regions of lowest velocity flow were 0.05 m/s. The magnitude of peak velocity flow on the aortic wall was not different between a single pair versus multiple pairs of side holes. Maximum velocity flow on the aortic wall occurred earlier at a lower pump flow rate in the vertical orientation of distal side holes compared to a horizontal position. The presence of multiple paired side holes was associated with fewer low-velocity flow regions, and some retrograde flow, in the distal abdominal aorta compared to cannulae with a single pair of side holes. From this in vitro visualization study, the selection of a cannula design with multiple versus single pairs of side holes did not change the magnitude of peak velocity flow delivered to the vessel wall. Cannulae with multiple side holes were associated with fewer regions of low-velocity flow in the distal abdominal aorta. Further in vivo studies, and ideally clinical data would be required to assess any correlation of peak velocity flows with incidence of vascular injury, and any low-velocity flow regions with incidence of thrombosis., (© 2020 International Center for Artificial Organs and Transplantation and Wiley Periodicals LLC.)

Accurate quantification and characterization of atherosclerotic plaques with MRI requires high spatial resolution acquisitions with excellent image quality. The intrinsically better signal-to-noise ratio (SNR) at high-field clinical 7T compared to the widely employed lower field strengths of 1.5 and 3T may yield significant improvements to vascular MRI. However, 7T atherosclerosis imaging also presents specific challenges, related to local transmit coils and B1 field inhomogeneities, which may overshadow these theoretical gains. We present the development and evaluation of 3D, black-blood, ultra-high resolution vascular MRI on clinical high-field 7T in comparison lower-field 3T. These protocols were applied for in vivo imaging of atherosclerotic rabbits, which are often used for development, testing, and validation of translatable cardiovascular MR protocols. Eight atherosclerotic New Zealand White rabbits were imaged on clinical 7T and 3T MRI scanners using 3D, isotropic, high (0.63 mm3) and ultra-high (0.43 mm3) spatial resolution, black-blood MR sequences with extensive spatial coverage. Following imaging, rabbits were sacrificed for validation using fluorescence imaging and histology. Image quality parameters such as SNR and contrast-to-noise ratio (CNR), as well as morphological and functional plaque measurements (plaque area and permeability) were evaluated at both field strengths. Using the same or comparable imaging parameters, SNR and CNR were in general higher at 7T compared to 3T, with a median (interquartiles) SNR gain of +40.3 (35.3-80.1)%, and a median CNR gain of +68.1 (38.5-95.2)%. Morphological and functional parameters, such as vessel wall area and permeability, were reliably acquired at 7T and correlated significantly with corresponding, widely validated 3T vessel wall MRI measurements. In conclusion, we successfully developed 3D, black-blood, ultra-high spatial resolution vessel wall MRI protocols on a 7T clinical scanner. 7T imaging was in general superior to 3T with respect to image quality, and comparable in terms of plaque area and permeability measurements., Competing Interests: The authors have read the journal's policy and have the following competing interests: IS is a paid employee of Takeda Pharmaceutical Company Limited, and HD is a paid employee of Hyperfine Research Inc. There are no patents, products in development or marketed products associated with this research to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background/purpose: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as an alternative technique for traumatic hemorrhage control in the adult population. The purpose of this study is to describe the details of REBOA placement in adolescent trauma patients., Methods: Patients 18 years of age or less who received REBOA for aortic occlusion (AO) from August 2013 to February 2017 at 2 urban tertiary care centers were included., Results: 7 adolescent trauma patients received REBOA by trauma surgeons for both blunt (n = 4) and penetrating mechanisms (n = 3); mean age was 17 + 1.5 years, mean admission lactate 13.0 + 4.85 mmol/L, and mean Hgb 10.7 + 2.7 g/dL. 3 patients received REBOA through a 12Fr sheath and 4 through a 7Fr sheath. AO occurred mostly at the distal thoracic aorta (Zone I) (85.7%) and also in the distal abdominal aorta (Zone III) (14.3%). 57% of patients were in arrest with ongoing CPR at the time of REBOA. In-hospital mortality was 57%; all of these patients were in arrest at the time of REBOA, had return of spontaneous circulation (ROSC), and survived to the operating room. No complications from REBOA were identified., Conclusion: REBOA appears to be feasible for use in adolescents despite their smaller caliber vessels, even with use of a 12Fr sheath. REBOA results in improved physiology and can bridge adolescent trauma patients presenting in extremis to the operating room., Type of Study: Treatment/therapeutic study LEVEL OF EVIDENCE: Level IV., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objectives: Penetrating abdominal aortic injury (PAAI) is a highly acute injury requiring prompt surgical management. When compared to surgeons at level-II trauma centers, surgeons at level-I trauma centers are more likely to take in-house call, and may more often be available within 15 minutes of patient arrival. Thus, we hypothesized that level-I trauma centers would have a lower mortality rate than level-II trauma centers in patients with PAAI., Methods: We queried the Trauma Quality Improvement Program database for patients with PAAI, and compared patients treated at American College of Surgeons (ACS)-verified level-I centers to those treated at ACS level-II centers., Results: PAAI was identified in 292 patients treated at level-I centers and 86 patients treated at level-II centers. Patients treated at the 2 center types had similar median age, injury severity scores and prevalence of diabetes, hypertension, and smoking (p > 0.05). There was no difference in the frequency of additional intra-abdominal vascular injuries (p > 0.05). Median time to hemorrhage control (level-I: 40.8 vs level-II: 49.2 minutes, p = 0.21) was similar between hospitals at the 2 trauma center levels. We found no difference in the total hospital length of stay or post-operative complications (p > 0.05). When controlling for covariates, we found no difference in the risk of mortality between ACS verified level-I and level-II trauma centers (OR:1.01, CI:0.28-2.64, p = 0.99)., Conclusion: Though the majority of PAAIs are treated at level-I trauma centers, we found no difference in the time to hemorrhage control, or the risk of mortality in those treated at level-I centers when compared to those treated at level-II trauma centers. This finding reinforces the ACS-verification process, which strives to achieve similar outcomes between level-I and level-II centers.

Background: "Seat belt-type" pediatric abdominal aortic trauma is uncommon but potentially lethal. During high speed motor vehicle collisions (MVCs), seat or lap belt restraints may concentrate forces in a band-like pattern across the abdomen, resulting in the triad of hollow viscus perforation, spine fracture, and aortoiliac injury. We report 4 cases of pediatric seat belt-type aortic trauma and review management strategies for the aortic disruption and the associated constellation of injuries., Methods: -approved, retrospective review of all pediatric patients requiring surgical intervention for seat belt-type constellation of abdominal aortic/iliac and associated injuries over a 5-year period. Blunt thoracic aortic injuries were excluded., Results: We identified 4 patients, ranging from 2 to 17 years of age, who required surgical correction of seat belt-type aortoiliac trauma and associated injuries: 3 abdominal aortas and 1 left common iliac artery. The majority (3/4 patients) were hemodynamically unstable at emergency room presentation, and all underwent computed tomography angiography of the chest/abdomen/pelvis during initial resuscitation. Injuries of the suprarenal and proximal infrarenal aorta were accompanied by unilateral renal artery avulsion requiring nephrectomy. Presumed or proven spinal instability mandated supine positioning and midline laparotomy, with medial visceral rotation utilized for proximal injuries. Aortoiliac injuries requiring repair were accompanied by significant distal intraluminal prolapse of dissected intima, with varying degrees of obstruction. Conduit selection was dictated by the presence of enteric contamination and the rapid availability of an autologous conduit. The sole neurologic deficit was irreparable at presentation., Conclusions: Seat belt aortoiliac injuries in pediatric patients require prompt multidisciplinary evaluation. Evidence of contained aortoiliac transection, major branch vessel avulsion, and bowel perforation mandates immediate exploration, which generally precedes spinal interventions. Lesser degrees of aortoiliac injuries have been managed with surveillance, but long-term follow-up is needed to fully validate this approach., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: Seat belt aorta is rare and difficult to manage. The lack of data and follow-up increases the complexity of treating such patients. We aimed to create a decision algorithm by reviewing our current experience and analyzing the presentation and management of our patients., Methods: We performed a descriptive case series based on retrospective analysis of all consecutive patients admitted with the diagnosis of seat belt aorta from 2008 to 2018. Seat belt aorta was defined as any blunt abdominal aortic lesion resulting from a seat belt compression mechanism after a car accident., Results: Nine consecutive patients were admitted with the diagnosis of seat belt aorta, all of whom developed lesions in the infrarenal aorta. Eight patients were assessed in the acute phase and one patient presented with late-onset symptoms. Associated injuries were present in all acute patients, and seat belt sign and small bowel injury were present in 88%. One patient presented with a small intimal tear and was treated conservatively. All other patients diagnosed with large intimal flaps (seven patients) and pseudoaneurysm (one patient) underwent open repair in five cases and endovascular repair in three cases. In-hospital mortality for the acute cases was 38%, with no mortality seen during follow-up. Two patients submitted to endovascular repair required reinterventions., Conclusions: Seat belt aorta is a deadly condition, frequently associated with blunt thoracoabdominal trauma with concomitant injuries; the presence of a seat belt sign or lower limb ischemia must lead to a high diagnostic suspicion. Management must take into account the other concomitant injuries. Follow-up is crucial as most patients are young; they may develop complications and subsequently require further intervention., (Copyright © 2019 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Abdominal aortic injury secondary to blunt abdominal aortic trauma (BAAI) is rare in children but frequently occurs in association with other injuries, including bowel injury and vertebral fracture. We present a case of a 14-year-old boy who sustained a partial transection of the infrarenal aorta with a lumbar chance fracture and small bowel injury after a motor vehicle accident. Repair was performed with bowel resection followed by Dacron graft interposition. We reviewed the literature on BAAI in children with a focus on the method of repair of these injuries., (Copyright © 2020. Published by Elsevier Inc.)

Objective: Blunt abdominal aortic injury (BAAI) occurs in less than 0.1% of blunt traumas. A previous multi-institutional study found an associated mortality rate of 39%. We sought to identify risk factors for BAAI and risk factors for mortality in patients with BAAI using a large national database. We hypothesized that an Injury Severity Score of 25 or greater, and thoracic trauma would both increase the risk of mortality in patients with BAAI., Methods: The Trauma Quality Improvement Program (2010-2016) was queried for individuals with blunt trauma. Patients with and without BAAI were compared. Covariates were included in a multivariable logistic regression model to determine mechanisms of injury, examination findings, and concomitant injuries associated with increased risk for BAAI. An additional multivariable analysis was performed for mortality in patients with BAAI., Results: From 1,056,633 blunt trauma admissions, 1012 (0.1%) had BAAI. The most common mechanism of injury was motor vehicle accident (MVA; 57.5%). More than one-half the patients had at least one rib fracture (54.0%), or a spine fracture (53.9%), whereas 20.8% had hypotension on admission and 7.8% had a trunk abrasion. The average length of stay was 13.4 days and 24.6% required laparotomy, with 6.6% receiving an endovascular repair and 2.9% an open repair. The risk of death in those treated with endovascular vs open repair was similar (P = .28). On multivariable analysis, MVA was the mechanism associated with the highest risk of BAAI (odds ratio [OR], 4.68; 95% confidence interval [CI], 3.87-5.65; P < .001) followed by pedestrian struck (OR, 4.54; 95% CI, 3.47-5.92; P < .001). Other factors associated with BAAI included hypotension on admission (OR, 3.87; 95% CI, 3.21-4.66; P < .001), hemopneumothorax (OR, 3.67; 95% CI, 1.16-11.58; P < .001), abrasion to the trunk (OR, 1.49; 95% CI, 1.15-1.94; P = .003), and rib fracture (OR, 1.46; 95% CI, 1.25-1.70; P < .001). The overall mortality rate was 28.0%. Of the variables examined, the strongest risk factor associated with mortality in patients with BAAI was hemopneumothorax (OR, 12.49; 95% CI, 1.25-124.84; P = .03) followed by inferior vena cava (IVC) injury (OR, 12.05; 95% CI, 2.80-51.80; P < .001)., Conclusions: In the largest nationwide series to date, BAAI continues to have a high mortality rate with hemopneumothorax and IVC injury associated with the highest risk for mortality. The mechanism most strongly associated with BAAI is MVA followed by pedestrian struck. Other risk factors for BAAI include rib fracture and trunk abrasion. Providers must maintain a high suspicion of injury for BAAI when these mechanisms of injury, physical examination or imaging findings are encountered., (Copyright © 2019 Society for Vascular Surgery. All rights reserved.)

Paediatric aortic trauma is a rare injury which can be fatal if not identified and managed appropriately. Surgical repair remains the gold-standard in moderate to severe aortic injuries. In the last decade however, endovascular treatment has gained popularity in children who have suitable vascular anatomy for intervention and are either not fit for surgery or in whom, endovascular intervention is the only alternative that will make a difference in the clinical outcome. Children pose a unique set of challenges to endovascular therapy. In this article, we aim to illustrate the different endovascular options that are available for the treatment of acute traumatic aortic injury and visceral thromboembolisation through pictorial representation. We will also demonstrate the feasibility and the limitation of this technique.

Trocar injury to abdominal aorta is uncommon and even rare with optical trocars. Such injury, resulting from umbilical trocar insertion, is potentially fatal. It often causes on-table death due to torrential life-threatening haemorrhage and unavailability of expert vascular help. We present a rare case of an injury to infra-renal abdominal aorta, caused by optical trocar insertion for bariatric surgery. Immediate recognition of the injury, deployment of life-saving manoeuvres, timely resuscitation, followed by definitive repair of aorta by vascular surgeon was life-saving for this patient. The recovery phase was uneventful and patient had no residual clinical problems during follow-up.

Competing Interests: Competing interests: None declared.

In cases of severe subdiaphragmatic vascular trauma, only in extremis interventions such as emergency thoracotomy with aortic cross clamping or resuscitative endovascular balloon occlusion of the aorta are available for temporization until definitive care. This case report proposes a noninvasive approach consisting of localizing the proximal aorta with ultrasonographic guidance and applying a compressive force to occlude the aorta and limit distal flow. Using point-of-care ultrasonography allows precise compression, continuous monitoring of its efficacy, and early detection of return of spontaneous circulation in arrest patients. We present the case of a patient who sustained a gunshot wound causing a left iliac artery injury and subsequent cardiac arrest while he was on route to the hospital. Point-of-care ultrasonographically guided proximal external aortic compression was attempted and return of spontaneous circulation was achieved and maintained, allowing transfer of the patient to the operating room. This single-case report suggests that point-of-care ultrasonographically guided proximal external aortic compression could be used as a bridge to definitive care or to more advanced techniques such as resuscitative endovascular balloon occlusion of the aorta and emergency department thoracotomy with aortic cross clamping., (Copyright © 2019 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.)

Background: Abdominal aortic injury (AAI) is a life-threatening condition that occurs in only 0.1% of all trauma admissions. Because of its rarity, the clinical features of AAI remain unclear. We investigated the characteristics, treatments, and clinical outcomes among patients with AAI., Methods: This retrospective cohort study was performed using the Japanese Diagnosis Procedure Combination database. We identified patients with a confirmed diagnosis of AAI with emergency admission from 1 July 2010 to 31 March 2017. Eligible patients were divided into three groups: those who were treated with no surgery or endovascular treatment (non-repair group), those who underwent surgery without endovascular treatment (open repair group), and those who received endovascular treatment without surgery (endovascular repair group)., Results: A total of 238 patients met the inclusion criteria during the study period. Of these, 191 (80.3%) were allocated to the non-repair group, 20 (8.4%) were allocated to the open repair group, and 27 (11.3%) were allocated to the endovascular repair group. The proportions of patients in the non-repair group from July 2010 to March 2012, April 2012 to March 2014, April 2014 to March 2016, and April 2016 to March 2017 were 93.5%, 75.9%, 80.6%, and 73.2%, respectively. The crude in-hospital mortality rate was 26.2%, 35.0%, and 18.5% in the non-repair, open repair, and endovascular repair group, respectively., Conclusions: In this cohort, the proportion of non-repair for AAI decreased from 2010 to 2017, whereas the proportion of endovascular repair increased. Younger patients were more likely to undergo open repair, whereas older patients were more likely to undergo endovascular repair., Competing Interests: Competing interestsThe authors declare that they have no competing interests.

Background: At present, bicortical pedicle screws (BPSs) are not used clinically because they carry the potential risk of damaging the prevertebral great vessels (PGVs). The authors observed the anatomical relationship between the PGVs and simulated BPSs at different transverse screw angles (TSAs), exploring the insertion method of the BPS., Methods: Computed tomography angiography (CTA) images from 65 adults were collected. A total of 4-5 TSAs of the BPSs were simulated on the left and right sides of L1-L5 (L1-L3: 0°, 5°, 10°, 15°; L4-L5: 0°, 5°, 10°, 15°, 20°). There were three types of distances from the anterior vertebral cortex (AVC) to the PGVs (D AVC-PGV ); D AVC-PGV < 0.50 cm , D AVC-PGV ≥ 0.50 cm , and D AVC-PGV↑ ; these distances represented close, distant, and noncontact PGV, respectively., Results: The ratio of every type of PGV was calculated, and the appropriate TSA of the BPS was recommended. In L1, the recommended left TSA of the BPS was 0°, and the ratio of the close PGV was 7.69%, while the recommended right TSA was 0°-10°, and the ratio of the close PGV was 1.54-4.62%. In L2, the recommended left TSA of the BPS was 0° and the ratio of the close PGV was 1.54%, while the recommended right TSA was 0°-15° and the ratio of the close PGV was 3.08-9.23%. In L3, the recommended left TSA was 0°-5°, and the ratio of the close PGV was 1.54-4.62%. In L4, the recommended left TSA was 0°, and the ratio of the close PGV was 4.62%. BPS use was not recommended on the right side of either L3 or L4 or on the either side of L5., Conclusions: From the anatomical perspective of the PGVs, BPSs were not suitable for insertion into every lumbar vertebra. Furthermore, the recommended methods for inserting BPSs were different in L1-L4.

Background: To further strengthen the evidence base on the use of Resuscitative Endovascular Balloon occlusion of the Aorta (REBOA) we performed a Delphi consensus. The aim of this paper is to establish consensus on the indications and contraindications for the use of REBOA in trauma and non-trauma patients based on the existing evidence and expertise., Study Design: A literature review facilitated the design of a three-round Delphi questionnaire. Delphi panelists were identified by the investigators. Consensus was reached when at least 70% of the panelists responded to the survey and more than 70% of respondents reached agreement or disagreement., Results: Panel members reached consensus on potential indications, contra-indications and settings for use of REBOA (excluding the pre hospital environment), physiological parameters for patient selection and indications for early femoral access. Panel members failed to reach consensus on the use of REBOA in patients in extremis (no pulse, no blood pressure) and the use of REBOA in patients with two major bleeding sites., Conclusions: Consensus was reached on indications, contra indications, physiological parameters for patient selection for REBOA and early femoral access. The panel did not reach consensus on the use of REBOA in patients in pre-hospital settings, patients in extremis (no pulse, no blood pressure) and in patients with 2 or more major bleeding sites. Further research should focus on the indications of REBOA in pre hospital settings, patients in near cardiac arrest and REBOA inflation times., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Importance: The need for improved methods of hemorrhage control and resuscitation has resulted in a reappraisal of resuscitative endovascular balloon occlusion of the aorta (REBOA). However, there is a paucity of data regarding the use of REBOA on a multi-institutional level in the United States., Objective: To evaluate the outcomes in trauma patients after REBOA placement., Design, Setting, and Participants: A case-control retrospective analysis was performed of the 2015-2016 American College of Surgeons Trauma Quality Improvement Program data set, a national multi-institutional database of trauma patients in the United States. A total of 593 818 adult trauma patients (aged ≥18 years) were analyzed and 420 patients were matched and included in the study; patients who were dead on arrival or were transferred from other facilities were excluded. Trauma patients who underwent REBOA placement in the ED were identified and matched with a similar cohort of patients (the no-REBOA group). Both groups were matched in a 1:2 ratio using propensity score matching for demographics, vital signs, mechanism of injury, injury severity score, head abbreviated injury scale score, each body region abbreviated injury scale score, pelvic fractures, lower extremity vascular injuries and fractures, and number and grades of intra-abdominal solid organ injuries., Main Outcomes and Measures: Outcome measures were the rates of complications and mortality., Results: Of 593 818 trauma patients, 420 patients (the REBOA group, 140 patients; 36 women and 104 men; mean [SD] age, 44 [20] years; the no-REBOA group, 280 patients; 77 women and 203 men; mean [SD] age, 43 [19] years) were matched and included in the analysis. Among the REBOA group, median injury severity score was 29 (interquartile range [IQR], 18-38) and 129 patients (92.1%) had a blunt mechanism of injury. There was no significant difference between groups in median 4-hour blood transfusion (REBOA: packed red blood cells, 6 U [IQR, 3-8 U]; platelets, 4 U [IQR, 3-9 U], and plasma, 3 U [IQR, 2-5 U]; and no-REBOA: packed red blood cells, 7 U [IQR, 3-9 U]; platelets, 4 U [IQR, 3-8 U], and plasma, 3 U [IQR, 2-6 U]) or 24-hour blood transfusion (REBOA: packed red blood cells, 9 U [IQR, 5-20 U]; platelets, 7 U [IQR, 3-13 U], and plasma, 9 U [IQR, 6-20 U]; and no-REBOA: packed red blood cells, 10 U [IQR, 4-21 U]; platelets, 8 U [IQR, 3-12 U], and plasma, 10 U [IQR, 7-20 U]), median hospital length of stay (REBOA, 8 days [IQR, 1-20 days]; and no-REBOA, 10 days [IQR, 5-22 days]), or median intensive care unit length of stay (REBOA, 5 days [IQR, 2-14 days]; and no-REBOA, 6 days [IQR, 3-15 days]). The mortality rate was higher in the REBOA group as compared with the no-REBOA group (50 [35.7%] vs 53 [18.9%]; P = .01). Patients who underwent REBOA placement were also more likely to develop acute kidney injury (15 [10.7%] vs 9 [3.2%]; P = .02) and more likely to undergo lower extremity amputation (5 [3.6%] vs 2 [0.7%]; P = .04)., Conclusions and Relevance: Placement of REBOA in severely injured trauma patients was associated with a higher mortality rate compared with a similar cohort of patients with no placement of REBOA. Patients in the REBOA group also had higher rates of acute kidney injury and lower leg amputations. There is a need for a concerted effort to clearly define when and in which patient population REBOA has benefit.

Competing Interests: Competing interests: None declared.

Competing Interests: None

Objective: Recent studies have demonstrated an increase in trauma mortality relative to mortality from cancer and heart diseases in the United States. Major vascular injuries such as to the inferior vena cava (IVC) and aortic injuries remain responsible for a significant proportion of early trauma deaths in modern trauma care. The purpose of this study was to explore patterns in epidemiology and mortality after IVC and aortic injuries in the United States., Methods: A 13-year analysis of the National Trauma Databank (2002-2014) was performed to extract all patients who sustained IVC, abdominal aortic, or thoracic aortic injuries. Demographics, clinical data, and outcomes were extracted. Patients were analyzed according to injury mechanism., Results: A total of 25,428 patients were included in this analysis. Overall, the mean age was 39.8 ± 19.1 years, 70.3% were male, and 14.1% sustained a penetrating trauma. Although the incidence of all three injuries remained constant throughout the study period, for blunt trauma, mortality decreased over the study period (from 48.8% in 2002 to 28.7% in 2014; P < .001), in particular for thoracic aortic injuries (from 46.1% in 2002 to 23.7% in 2014; P < .001) and abdominal aortic injuries (from 58.3% in 2002 to 26.2% in 2014; P < .001). This decrease in mortality after blunt trauma was accompanied by an increase in endovascular procedures over the study period (from 1.0% in 2002 to 30.4% in 2014; P < .001), in particular for blunt thoracic aortic injuries (from 0.7% in 2002 to 41.4% in 2014; P < .001). When penetrating trauma patients were analyzed, overall there was an increase in mortality (from 43.8% in 2002 to 50.6% in 2014; P < .001), in particular after abdominal aortic injury (from 30.4% in 2002 to 66.0% in 2014; P < .001). Similar trends were observed for IVC injuries. No increase in endovascular use in penetrating trauma was identified (from 0.1% in 2002 to 3.4% in 2014; P < .001)., Conclusions: The present study demonstrates an overall decrease in mortality after blunt aortic injuries in the United States. This decrease was accompanied by an increase in the use of endovascular procedures. After penetrating trauma, however, despite contemporary advances in trauma care, mortality has increased over the study period, in particular after abdominal aortic injury. No increase in endovascular use in penetrating trauma was demonstrated., (Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Blunt abdominal aortic injuries are extremely rare, diagnosed in less than 0.05% of all trauma admissions. Aortic injury caused by a seat belt during a car accident is often referred as "seat-belt aorta". We present a case of an 18-year-old woman, restrained back passenger involved in a vehicular collision, sustaining vertebral column and multiple rib fractures, mesenterium and colonic injury, and infrarenal aortic contusion with localized dissection and partial thrombosis., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Blunt abdominal aortic injury (BAAI) is extremely rare. Three known treatments of BAAI exist: medical treatment, conventional surgical treatment, and endovascular treatment. Outcomes of medical and conventional surgical treatments, such as bypass graft, thrombectomy, and intimal suture, were not satisfactory. A 47-year-old man presented with multiple injuries after a high-speed vehicular accident. He was diagnosed with the traumatic aortic injury to be an intra-mural hematoma in the bifurcation of the terminal aorta. Endovascular repair with a kissing stent was performed after exploratory laparotomy. At 12 months postoperatively, the kissing stents were patent and intact, and there was no late complication. The findings indicate that the kissing stent could be useful for the treatment of BAAI in the terminal aorta.

Background: Traumatic injuries to the pelvis and high junctional injuries are difficult to treat in the field; however, Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) and the Abdominal Aortic and Junctional Tourniquet (AAJT) constitute two promising treatment modalities. The aim of this study is to use a large animal model of pelvic hemorrhage to compare the survival, hemostatic, hemodynamic, and metabolic profile of both techniques., Methods: Yorkshire swine (n = 10, 70-90 kg) underwent general anesthesia, instrumentation, and surgical isolation of the femoral artery. Uncontrolled hemorrhage was initiated by an arteriotomy. Animals were randomly allocated to either REBOA or AAJT. Following completion of device application, both groups received a 500 mL Hextend bolus. After 1 hour, the injured femoral artery was ligated to simulate definitive hemostasis followed by a second Hextend bolus and device removal. Animals were observed for two more hours. Physiological data were collected throughout the experiments and compared between groups., Results: Both techniques achieved 100% hemostasis, and all animals survived the entire experiment except one in the REBOA group. During the hour treatment phase, the AAJT group had a higher mean arterial pressure than the REBOA group (59.9 ± 16.1 versus 44.6 ± 9.8 mm Hg, respectively; P < 0.05). The AAJT-treated group had higher lactate levels than the REBOA-treated group (4.5 ± 2.0 versus 3.2 ± 1.3 mg/dL, respectively; P < 0.05)., Conclusions: Despite their mechanistic differences, both techniques achieved a similar hemostatic, hemodynamic, and metabolic profile. Some differences do exist including lactate levels and blood pressure., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Blunt traumatic abdominal aortic injury in children is a rare but a severe condition. The clinical manifestation often involves other intra-abdominal visceral injuries and vertebral fractures. The best therapeutic management is still unclear with few reported endovascular cases treated. The following is the case of a 13-year-old male with an aortic abdominal dissection, spleen laceration, jejunal contusion, and hemoperitoneum after a motor vehicle collision. An endovascular approach was decided upon after the progression of the intimal aortic tear. A self-expanding stent was implanted into the injured position with an immediate proximal migration to the visceral aorta. It was decided not to retrieve the stent because of added comorbidity, and an open repair of the dissection was performed using a graft bypass. The patient has completed a 6-year image surveillance without complications or growth alterations. To our knowledge, this is the first reported childhood case of an intraoperative stent migration during the endovascular treatment of a blunt traumatic abdominal aortic injury. The possible cause of the complication and the management of these kinds of injuries are reviewed in detail in this article., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Composite vascular patches have gained increasingly attention due to the limited availability of autologous patches (vascular graft materials made from the blood vessels of the same recipient), the lack of growth capability of nonautologous patches (vascular graft materials made from the blood vessels of a different donor) and the disadvantages of synthetic patches. In this study, we report a highly biocompatible phosphatidylcholine-polyurethane nanoparticle/polyurethane/decellularized scaffold composite vascular patch (PCVP). It was fabricated by a facile method - cosedimentation. Its in vitro blood and cell compatibility including hemolysis, plasma recalcification time, coagulation time, platelet adhesion and cytotoxicity was evaluated. The surface modified with phosphatidylcholine-polyurethane (PC-PU) nanoparticles exhibited the improved anticoagulation activity. The in vivo performance of the PCVP was investigated in a mouse model. The nanopatterned surface that resembled the concave-convex structure of the luminal surface of native blood vessels enhanced cell attachment, proliferation, migration and differentiation. The decellularized scaffold had the mechanical property similar to that of the targeted blood vessels, which could withstand in vivo dynamic blood pressure. The overall performance of the PCVP was synergistically optimized by each layer of the multilayer design. The patched artery remained patent and the formation of endothelial tissue - endothelialization was achieved 30days after the in vivo implantation in a mouse model., (Copyright © 2017 Elsevier B.V. All rights reserved.)

To assess the elastic mechanical properties of atherosclerotic plaque with different morphological properties by intravascular ultrasound elastography (IVUSE). 30 purebred New Zealand rabbits were fed a high-cholesterol diet; the abdominal aorta endothelium was balloon-injured after 2 weeks; at week 12, 2 plaques with moderate echo from each rabbit were chosen for in situ imaging, and 2 consecutive frames near the end-diastole images in situ were used to construct an IVUS elastogram. Shear strain (SS) and area strain (AS) were greater for eccentric than centripetal plaque (SS: 2.65(2.45)% vs. 1.79 ± 0.97%, p < 0.05; AS: 4.81(4.99)% vs. 3.23 ± 1.75%, p < 0.05) but were lower with low than high plaque burden (SS: 2.14 ± 0.37% vs. 3.40 ± 0.34%, p < 0.05; AS: 3.88 ± 0.60% vs. 5.81 ± 0.54%, p < 0.05). SS and AS were significantly greater for plaque with negative than no remodeling (SS: 3.98 ± 1.53% vs. 1.82(1.40)%, p < 0.017; AS: 6.94 ± 2.24% vs. 2.59(2.87)%, p < 0.017) and were found correlated with eccentric index and plaque burden (R 2  = 0.365 and R 2  = 0.359, both p < 0.05). Plaques associated with eccentricity, high plaque burden and negative remodeling showed greater strain than those with centripetalism, low plaque burden and positive remodeling. Eccentric index and plaque burden may be useful to predict the elastic stability of plaque.

We present a patient with blunt abdominal trauma with severe acute right limb ischemia and clinical signs of diffuse peritonitis. Computed tomography angiography showed circumferential dissection of the infrarenal aorta with occlusion of the right common iliac artery. We opted for simultaneous abdomen exploration and open repair of injured aorta. Critical weakening of the aortic wall with imminent rupture was identified intraoperatively. Aortotomy cranially from bifurcation showed circumferential intimomedial dissection. The fixation of fragile intimomedial flap of aortic dissection was achieved with reinforcement using an anterior longitudinal ligament. The long aortoiliac arteriotomy was repaired using a great saphenous vein patch. Patient had uneventful postoperative course and was discharged after 7 days. In patients with abdominal polytrauma with peritonitis, and no available endovascular tools, open surgery for circumferential aortic dissection is possible and successful. Described reinforcement of the posterior aortic wall to the anterior longitudinal ligament should be added to the armamentarium of aortic injury treatment.

We herein report an uncommon case of a life-threatening retroperitoneal hematoma after a bone marrow biopsy. Two hours after iliac crest bone harvesting, the patient experienced syncope and severe hypotension. Urgent contrast-enhanced computed tomography demonstrated extravasation from the superior gluteal artery. Transcatheter coil embolization was performed successfully, without complications. Life-threatening complications caused by retroperitoneal bleeding after bone marrow biopsy are very rare. There are few reports on the use of endovascular treatment in the management of life-threatening hemorrhagic complications after bone marrow biopsy.

Background: Standard cardiopulmonary resuscitation (CPR) is ineffective in treating traumatic cardiac arrest (TCA) following hemorrhagic shock despite fluid resuscitation. CPR adjuncts, including abdominal compressions and external counter pressure, have shown some success in laboratory settings. The Abdominal Aortic and Junctional Tourniquet (AAJT) is a device that occludes both venous and arterial blood at the level of the aortic bifurcation and likely increases thoracic pressure when applied to the abdomen. We developed a swine model of controlled hemorrhage to induce a state of TCA to test the ability of the AAJT to improve the efficacy of CPR., Methods: Twelve splenectomized, Yorkshire, male swine (70-90 kg) were randomized into two groups: presence or absence of AAJT placement. Controlled hemorrhage was performed at a rate of 2 mL/kg/min until systolic blood pressure reached below 10 mm Hg (defined as cardiac arrest). Following 3 minutes of arrest, the animals underwent CPR using a mechanical compression device along with either the presence or absence of the AAJT. Concurrently, 5 units of whole blood (2,500 mL) were delivered through the jugular vein at 500 mL/min. Efficacy of CPR was assessed by analyzing rates of return of spontaneous circulation (ROSC) and survival. Blood pressure, carotid blood flow, and other hemodynamic values were also compared., Findings: No significant differences between groups were observed before treatments. The controlled hemorrhage resulted in an average loss of 2,654 ± 323 g of blood over 18.2 ± 3.9 minutes. All animals that had a ROSC survived to the end of the 1-hour observation period. Animals with AAJT survived 83% (5/6) compared to 17% (1/6) of animals without AAJT. Finally, blood pressure, carotid flow, mean pulmonary artery pressure, and end tidal carbon dioxide were all significantly different between groups at the end of the first 10-minute compression period., Discussion/impact/recommendations: These results suggest that the AAJT could allow for increased CPR efficacy in cases of TCA when used in conjunction with rapid, massive blood transfusions., (Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.)

Background: Human saphenous veins used for arterial bypass undergo stretch injury at the time of harvest and preimplant preparation. Vascular injury promotes intimal hyperplasia, the leading cause of graft failure, but the molecular events leading to this response are largely unknown. This study investigated adenosine triphosphate (ATP) as a potential molecular mediator in the vascular response to stretch injury, and the downstream effects of the purinergic receptor, P2X7R, and p38 MAPK activation., Materials and Methods: A subfailure stretch rat aorta model was used to determine the effect of stretch injury on release of ATP and vasomotor responses. Stretch-injured tissues were treated with apyrase, the P2X7R antagonist, A438079, or the p38 MAPK inhibitor, SB203580, and subsequent contractile forces were measured using a muscle bath. An exogenous ATP (eATP) injury model was developed and the experiment repeated. Change in p38 MAPK phosphorylation after stretch and eATP tissue injury was determined using Western blotting. Noninjured tissue was incubated in the p38 MAPK activator, anisomycin, and subsequent contractile function and p38 MAPK phosphorylation were analyzed., Results: Stretch injury was associated with release of ATP. Contractile function was decreased in tissue subjected to subfailure stretch, eATP, and anisomycin. Contractile function was restored by apyrase, P2X7R antagonism, and p38-MAPK inhibition. Stretch, eATP, and anisomycin-injured tissue demonstrated increased phosphorylation of p38 MAPK., Conclusions: Taken together, these data suggest that the vascular response to stretch injury is associated with release of ATP and activation of the P2X7R/P38 MAPK pathway, resulting in contractile dysfunction. Modulation of this pathway in vein grafts after harvest and before implantation may reduce the vascular response to injury., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Introduction: The management of patients with abdominal aortic injury (AAI) remains challenging. Open repair of AAI is still the standard of care although it is associated with high mortality. In past few years, endovascular surgery has evolved as a less invasive alternative to open surgery in emergency settings. The objective of this study was to compare outcomes after open repair versus endovascular repair of AAI in polytrauma patients., Methods: The National Trauma Data Bank, from 2008 to 2012, was queried to identify trauma patients undergoing open and endovascular repair of AAI using International Classification of Diseases, ninth Edition, and Clinical Modification codes. Data reviewed included demographics, type of associated injury, type of operative management, and complications. Factors independently associated with mortality were evaluated using multivariate logistic regression model., Results: Of 325 injured patients with AAI, 91 patients underwent endovascular repair and 234 patients underwent open repair. Of these, 80.6% were male, with a mean age of 35.70 years, and a mean injury severity score (ISS) was 30.59 for patients undergoing open repair and 31.56 for endovascular repair. Associated traumatic injuries included bowel injuries 57.5%, liver-pancreas injuries 36.6%, splenic injuries 14.8%, renal injuries 15.7%, and retroperitoneal injuries 19.1%. In-patient mortality for patients undergoing the open repair cohort was 63.7% and 20.9% for patients in the endovascular cohort (P < 0.001). The endovascular repair cohort patients had a higher incidence of pneumonia 17.6% as compared to open repair cohort 5.1% (P < 0.001). Similarly, patients in the endovascular repair cohort also had a higher abdominal compartment syndrome (4.4% vs. 0.4% in the open repair cohort, P = 0.009), postoperative acute kidney injury (9.9% endovascular repair cohort vs. 6.4% in the open repair cohort, P = 0.281), and acute mesenteric ischemia (1.1%). After controlling for associated injuries, acidosis, blood pressure at presentation, age, and ISS, patients in the open repair cohort had 6.58 times higher odds (confidence interval: 3.25-13.33; P < 0.001) of mortality as compared to the endovascular repair cohort., Conclusions: Endovascular repair of abdominal aorta in polytrauma patients seems to be feasible and may improve survivorship in appropriately selected patients. More research is needed to understand to identify indications for endovascular repair versus open repair., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Arterial reconstruction, whether angioplasty or bypass surgery, involves iatrogenic trauma causing endothelial disruption and vascular smooth muscle cell (VSMC) proliferation. Common murine models study small vessels such as the carotid and femoral arteries. Herein we describe an in vivo system in which both VSMC proliferation and endothelial barrier function can be simultaneously assessed in a large vessel. We studied the infrarenal aortic response to injury in C57BL/6 mice. The aorta was injured from the left renal vein to the aortic bifurcation by 30 transmural crushes of 5-seconds duration with a cotton-tipped applicator. Morphological changes were assessed with conventional histology. Aorta wall thickness was measured from the luminal surface to the adventitia. EdU integration and counter staining with DAPI and alpha-actin was used to demonstrate VSMC proliferation. Activation of ERK1/2, a known moderator of intimal hyperplasia formation, was determined by Western Blot analysis. The effect of inflammation was determined by immunohistochemistry for B-cells, T-cells, and macrophages. En face sections of endothelium were visualized with scanning electron microscopy (SEM). Endothelial barrier function was determined with Evans Blue staining. Transmural injury resulted in aortic wall thickening. This injury induced VSMC proliferation, most prominently at 3 days after injury, and early activation of ERK1/2 and decreased p27 kip1 expression. Injury did not result in increased B-cells, T-cells, or macrophages infiltration in the vessel wall. Injury caused partial endothelial cell denudation and loss of cell-cell contact. Injury resulted in a significant loss of endothelial barrier function, which returned to baseline after seven days. The murine transmural blunt aortic injury model provides an efficient system to simultaneously study both VSMC proliferation and endothelial barrier function in a large vessel.

Balloon occlusion of the aorta was first described by C.W. Hughes in 1954, when it was used as a tamponade device for three wounded soldiers during the Korean War suffering from intra-abdominal hemorrhage. Currently, the device is indicated in trauma patients as a surrogate for resuscitative thoracotomy. Brenner et al. reported a case series describing the use of resuscitative endovascular balloon occlusion of the aorta (REBOA) in advanced hemorrhagic shock. Their conclusion was that "it is a feasible method for proximal aortic control." We describe the novel use of REBOA before retroperitoneal hematoma exploration in a hemodynamically unstable patient. Reported is a 19-year-old blunt trauma victim where REBOA was successfully deployed as a means for proximal arterial control before a Zone 1 retroperitoneal hematoma exploration. The source of the patient's hemorrhagic shock was multifactorial: grade V hepatic injury, retrohepatic inferior vena cava laceration, and right renal vein avulsion with Zone 1 retroperitoneal hematoma. Immediate return of perfusion pressure, as systolic pressures increased from 50 to 150 mm Hg. Hemodynamic improvements were accompanied by decreased transfusion and vasopressor requirements. In addition, the surgeons were able to enter the retroperitoneal hematoma under controlled conditions. REBOA is an attractive new tool to gain proximal aortic control in select patients with hemorrhagic shock. It is less morbid, possibly more efficient, and appears to be more effective than resuscitative thoracotomy. REBOA is certainly feasible for proximal aortic control before retroperitoneal exploration, and should be considered in select patients.

Background: Applying manual pressure after hemorrhage is intuitive, cost-free, and logistically-simple. When direct abdominal-pelvic compression fails, clinicians can attempt indirect proximal-external-aortic-compression (PEAC), while expediting transfer and definitive rescue. This study quantifies the sustainability of simulated bi-manual PEAC both immediately on scene and during subsequent ambulance transfer. The goal is to understand when bi-manual PEAC might be clinically-useful, and when to prioritize compression-devices or endovascular-occlusion., Methods: We developed a simulated central vessel compression model utilizing a digital scale and Malbrain intra-abdominal pressure monitor inside a cardiopulmonary resuscitation mannequin. Twenty prehospital health care professionals (HCPs) performed simulated bimanual PEAC i) while stationary and ii) inside an 80km/h ambulance on a closed driving-track. Participants compressed at "the maximal effort they could maintain for 20min". Results were measured in mmHg applied-pressure and kilograms compressive-weight. The Borg scale of perceived-exertion was used to assess sustainability, with <16 regarded as acceptable., Results: While stationary all participants could maintain 20min of compressive pressure/weight: within five-percent of their starting effort, and with a Borg-score <16. Participants applied 88-300mmHg compression pressure; (mean 180mmHg), 14-55kg compression-weight (mean 33kg), and 37-66% of their bodyweight (mean 43%). In contrast, participants could not apply consistent or sustained compression in a moving ambulance: Borg Score exceeded 16 in all cases., Conclusions: Survival following major abdominal-pelvic hemorrhage requires expedited operative/interventional rescue. Firstly, however, we must temporize pre-hospital exsanguination both on scene and during transfer. Despite limitations, our work suggests PEAC is feasible while waiting for, but not during, ambulance-transfer. Accordingly, we propose a chain-of-survival that cautions against over-reliance on manual PEAC, while supporting pre-hospital devices, endovascular occlusion, and expeditious but safe hospital-transfer., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Minimizing haemorrhage using direct pressure is intuitive and widely taught. In contrast, this study examines the use of indirect-pressure, specifically external aortic compression (EAC). Indirect pressure has great potential for temporizing bleeds not amenable to direct tamponade i.e. abdominal-pelvic, junctional, and multi-site trauma. However, it is currently unclear how to optimize this technique., Methods: We designed a model of central vessel compression using the Malbrain intra-abdominal pressure monitor and digital weigh scale. Forty participants performed simulated external aortic compression on the ground, on a stretcher mattress, and with and without a backboard., Results: The greater the rescuer's bodyweight the greater was their mean compression (Pearson's correlation 0.93). Using one-hand, a mean of 28% participant bodyweight (95% CI, 26-30%) could be transmitted at sustainable effort, waist-height, and on a stretcher. A second compressing hand increased the percentage of rescuer bodyweight transmission 10-22% regardless of other factors (i.e. presence/absence or a backboard; rescuer position) (p<0.001). Adding a backboard increased transmission of rescuer bodyweight 7-15% (p<0.001). Lowering the patient from waist-height backboard to the floor increased transmission of rescuer bodyweight 4-9% (p<0.001). Kneeling on the model was the most efficient method and transmitted 11% more weight compared to two-handed maximal compression (p<0.001)., Conclusions: Efficacy is maximized with larger-weight rescuers who use both hands, position themselves atop victims, and compress on hard surfaces/backboards. Knee compression is most effective and least fatiguing, thus assisting rescuers of lower weight and lesser strength, where no hard surfaces exist (i.e. no available backboard or trauma on soft ground), or when lengthy compression is required (i.e. remote locations). Our work quantifies methods to optimize indirect pressure as a temporizing measure following life-threatening haemorrhage not amenable to direct compression, and while expediting compression devices or definitive treatment., (Copyright © 2016 Elsevier Ltd. All rights reserved.)